Operation CHARM: Car repair manuals for everyone.

Engine RPM/Vehicle Speed Limiter

The Powertrain Control Module (PCM) will disable some or all of the fuel injectors whenever an engine rpm or vehicle overspeed condition is detected. The purpose of the engine rpm or vehicle speed limiter is to prevent damage to the powertrain. The vehicle will exhibit a rough running engine condition and the PCM will store a Continuous DTC P1270. Once the driver reduces the excessive speed, the vehicle will return to the normal operating mode. No repair is required. However, the technician should clear the PCM and inform the customer of the reason for the DTC.

Excessive wheel slippage may be caused by sand, gravel, rain, mud, snow, ice, etc. or over revving of the engine while in neutral or while driving.